view Lib/fftw-3.2.1/dft/bluestein.c @ 1:e86e9c111b29

Updates stuff that potentially fixes the memory leak and also makes it work on Windows and Linux (Need to test). Still have to fix fftw include for linux in Jucer.

/*
 * Copyright (c) 2003, 2007-8 Matteo Frigo
 * Copyright (c) 2003, 2007-8 Massachusetts Institute of Technology
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include "dft.h"

typedef struct {
     solver super;
} S;

typedef struct {
     plan_dft super;
     INT n;     /* problem size */
     INT nb;    /* size of convolution */
     R *w;      /* lambda k . exp(2*pi*i*k^2/(2*n)) */
     R *W;      /* DFT(w) */
     plan *cldf;
     INT is, os;
} P;

static void bluestein_sequence(enum wakefulness wakefulness, INT n, R *w)
{
     INT k, ksq, n2 = 2 * n;
     triggen *t = X(mktriggen)(wakefulness, n2);

     ksq = 0;
     for (k = 0; k < n; ++k) {
	  t->cexp(t, ksq, w+2*k);
          /* careful with overflow */
          ksq += 2*k + 1; while (ksq > n2) ksq -= n2;
     }

     X(triggen_destroy)(t);
}

static void mktwiddle(enum wakefulness wakefulness, P *p)
{
     INT i;
     INT n = p->n, nb = p->nb;
     R *w, *W;
     E nbf = (E)nb;

     p->w = w = (R *) MALLOC(2 * n * sizeof(R), TWIDDLES);
     p->W = W = (R *) MALLOC(2 * nb * sizeof(R), TWIDDLES);

     bluestein_sequence(wakefulness, n, w);

     for (i = 0; i < nb; ++i)
          W[2*i] = W[2*i+1] = K(0.0);

     W[0] = w[0] / nbf;
     W[1] = w[1] / nbf;

     for (i = 1; i < n; ++i) {
          W[2*i] = W[2*(nb-i)] = w[2*i] / nbf;
          W[2*i+1] = W[2*(nb-i)+1] = w[2*i+1] / nbf;
     }

     {
          plan_dft *cldf = (plan_dft *)p->cldf;
	  /* cldf must be awake */
          cldf->apply(p->cldf, W, W+1, W, W+1);
     }
}

static void apply(const plan *ego_, R *ri, R *ii, R *ro, R *io)
{
     const P *ego = (const P *) ego_;
     INT i, n = ego->n, nb = ego->nb, is = ego->is, os = ego->os;
     R *w = ego->w, *W = ego->W;
     R *b = (R *) MALLOC(2 * nb * sizeof(R), BUFFERS);

     /* multiply input by conjugate bluestein sequence */
     for (i = 0; i < n; ++i) {
	  E xr = ri[i*is], xi = ii[i*is];
          E wr = w[2*i], wi = w[2*i+1];
          b[2*i] = xr * wr + xi * wi;
          b[2*i+1] = xi * wr - xr * wi;
     }

     for (; i < nb; ++i) b[2*i] = b[2*i+1] = K(0.0);

     /* convolution: FFT */
     {
          plan_dft *cldf = (plan_dft *)ego->cldf;
          cldf->apply(ego->cldf, b, b+1, b, b+1);
     }

     /* convolution: pointwise multiplication */
     for (i = 0; i < nb; ++i) {
	  E xr = b[2*i], xi = b[2*i+1];
          E wr = W[2*i], wi = W[2*i+1];
          b[2*i] = xi * wr + xr * wi;
          b[2*i+1] = xr * wr - xi * wi;
     }

     /* convolution: IFFT by FFT with real/imag input/output swapped */
     {
          plan_dft *cldf = (plan_dft *)ego->cldf;
          cldf->apply(ego->cldf, b, b+1, b, b+1);
     }

     /* multiply output by conjugate bluestein sequence */
     for (i = 0; i < n; ++i) {
	  E xi = b[2*i], xr = b[2*i+1];
          E wr = w[2*i], wi = w[2*i+1];
          ro[i*os] = xr * wr + xi * wi;
          io[i*os] = xi * wr - xr * wi;
     }

     X(ifree)(b);	  
}

static void awake(plan *ego_, enum wakefulness wakefulness)
{
     P *ego = (P *) ego_;

     X(plan_awake)(ego->cldf, wakefulness);

     switch (wakefulness) {
	 case SLEEPY:
	      X(ifree0)(ego->w); ego->w = 0;
	      X(ifree0)(ego->W); ego->W = 0;
	      break;
	 default:
	      A(!ego->w);
	      mktwiddle(wakefulness, ego);
	      break;
     }
}

static int applicable0(const problem *p_)
{
     const problem_dft *p = (const problem_dft *) p_;
     return (1
	     && p->sz->rnk == 1
	     && p->vecsz->rnk == 0
	     /* FIXME: allow other sizes */
	     && X(is_prime)(p->sz->dims[0].n)

	     /* FIXME: infinite recursion of bluestein with itself */
	     && p->sz->dims[0].n > 16
	  );
}

static int applicable(const solver *ego, const problem *p_, 
		      const planner *plnr)
{
     UNUSED(ego);
     if (NO_SLOWP(plnr)) return 0;
     if (!applicable0(p_)) return 0;
     return 1;
}

static void destroy(plan *ego_)
{
     P *ego = (P *) ego_;
     X(plan_destroy_internal)(ego->cldf);
}

static void print(const plan *ego_, printer *p)
{
     const P *ego = (const P *)ego_;
     p->print(p, "(dft-bluestein-%D/%D%(%p%))",
              ego->n, ego->nb, ego->cldf);
}

static INT choose_transform_size(INT minsz)
{
     static const INT primes[] = { 2, 3, 5, 0 };
     while (!X(factors_into)(minsz, primes))
	  ++minsz;
     return minsz;
}

static plan *mkplan(const solver *ego, const problem *p_, planner *plnr)
{
     const problem_dft *p = (const problem_dft *) p_;
     P *pln;
     INT n, nb;
     plan *cldf = 0;
     R *buf = (R *) 0;

     static const plan_adt padt = {
	  X(dft_solve), awake, print, destroy
     };

     if (!applicable(ego, p_, plnr))
	  return (plan *) 0;

     n = p->sz->dims[0].n;
     nb = choose_transform_size(2 * n - 1);
     buf = (R *) MALLOC(2 * nb * sizeof(R), BUFFERS);

     cldf = X(mkplan_f_d)(plnr, 
			  X(mkproblem_dft_d)(X(mktensor_1d)(nb, 2, 2),
					     X(mktensor_1d)(1, 0, 0),
					     buf, buf+1, 
					     buf, buf+1),
			  NO_SLOW, 0, 0);
     if (!cldf) goto nada;

     X(ifree)(buf);

     pln = MKPLAN_DFT(P, &padt, apply);

     pln->n = n;
     pln->nb = nb;
     pln->w = 0;
     pln->W = 0;
     pln->cldf = cldf;
     pln->is = p->sz->dims[0].is;
     pln->os = p->sz->dims[0].os;

     X(ops_add)(&cldf->ops, &cldf->ops, &pln->super.super.ops);
     pln->super.super.ops.add += 4 * n + 2 * nb;
     pln->super.super.ops.mul += 8 * n + 4 * nb;
     pln->super.super.ops.other += 6 * (n + nb);

     return &(pln->super.super);

 nada:
     X(ifree0)(buf);
     X(plan_destroy_internal)(cldf);
     return (plan *)0;
}


static solver *mksolver(void)
{
     static const solver_adt sadt = { PROBLEM_DFT, mkplan, 0 };
     S *slv = MKSOLVER(S, &sadt);
     return &(slv->super);
}

void X(dft_bluestein_register)(planner *p)
{
     REGISTER_SOLVER(p, mksolver());
}